Extensible periscope



June17,1969 I SCLAVE ETAL 3,450,457

EXTENSIBLE PERISCOPE Filed March 9, 1964 Sheet or 4 June 17, 1969 s.CLAVE ETAL EXTENSIBLE PERI SCOPE Sheet 2, v0! 4 I Filed March 9, 1964June 17, 1969 s. CLAVE ET AL 3,450,457

EXTENSIBLE PERISCOPE Filed flank}. ,1964 Sheet n? a o! 4 United StatesPatent 3,450,457 EXTENSIBLE PERISCOPE Serge Clave and Marcel Clave, bothof 9 Rue Olivier-Metra, Paris, France Filed Mar. 9, 1964, Ser. No.350,396 Claims priority, application France, Mar. 11, 1963, 927,536 Int.Cl. G02b 23/08 U.S. Cl. 350-45 6 Claims ABSTRACT OF THE DISCLOSURE Inusing certain optical instruments such as periscopes or endoscopes, forexample, it is possible to observe zones lying at different levels or indifferent positions only by moving the apparatus until its objective isin axial alignment with the Zone to be observed.

When an operator Wishes to continuously examine different zones whichare adjacent to each other, he must then move in the same direction ashis optical instrument, and such movements are sometimes impractical ordifiicult to eflect.

The present invention relates to an optical device having an extensiblemounting comprising the different elements which form a one-pieceperiscope or endoscope distributed among the elements constituting anextensible mounting, and provided with mechanical means for transmittingto the level of a movable objective those movements necessary in thecourse of observation, while nevertheless permitting the eyepiece toremain stationary.

The mounting of our new optical device consists essentially of adeformable parallelogram made of four tubular members pivotallyconnected to each other at their ends, the objective of the instrumentbeing positioned at one corner of the parallelogram thus formed, whilethe opposite corner, which is attached to the stationary part of theinstrument, carries the eyepiece.

The new optical device is so arranged that the optical elements arespaced along the length of two consecutive tubes intervening between thesaid two corners of the parallelogram, while the mechanical memberswhich control the movement of certain of the optical elements, as forexample, the focussing of the objective, the pivoting of a prism, theinsertion of a filter, or the substitution of one objective for another,are mounted in the two other tubes constituting the parallelogram.

In the optical part, which is mounted in one half of the parallelogram,two totally reflecting mirrors or prisms are positioned at each of thepivot points and two plane mirrors, one of which is mounted in each ofsaid tubes, have their faces strictly parallel to each other.

This arrangement makes it possible to avoid any turning of the imageduring deformation of the parrallelogram, since the image is reflectedthrough the same angle regardless of the shape of the parallelogram atthe moment of observation.

The tubes also contain other optical elements, such as objectives andcollective members.

It is well known that the use of rotating prisms as panoramic objectivesleads to rotation of the image when the prism is rotated, and that thisrotation may be compensated for by turning a Dove type prism inserted inthe path of the light rays at an angle equal to half the angle ofrotation of the rotating prism.

In the device according to the present invention the rotating prism ispositioned in a box connecting the ends of two movable tubes, which boxalso carries the objective, while the compensating prism may bepositioned in either the fixed member connecting the ends of the twoother tubes or in one of the two tubes containing the optical elements.

The motion transmitting means mounted in the two other tubes arepreferably controlled by chains and sprockets so that the expansion orcontraction of the parallelogram has no influence thereon.

The objective may be displaced with respect to the eye piece, upward,for example, by extending the parallelogram in that direction only, thefour tubes remaining on the contrary, in the same relative horizontalposition. The displacement of the objective is then equal to the sum ofthe lengths of the two tubes. This is hereinafter referred to as asingle acting arrangement.

In another embodiment of the invention, which may be called the doubleacting mounting, the objective may be displacedwith respect to theeyeplace by extending the parallelogram on either side of its foldedposition, for example, vertically either up or down. In this case, thedisplacement of the objective may attain twice the total length of thetwo tubes.

It follows, that devices comprising several juxtaposed parallelogramsmay be constructed, for example, in order to provide binocularinstruments.

The characteristics of the present invention will be better understoodafter reading the following description of a single-acting monocularembodiment of our periscope, which embodiment is described purely by wayof example, in connection with the accompanying drawings, in which:

FIG. 1 is a perspective view of the apparatus, showing the variouscontrols;

FIG. 2 is a schematic view showing the path followed by the median rayof a pencil of light from the objective to the eyepiece;

FIG. 3 is an elevational view showing in particular the details of thevarious mechanical controls mounted in the box holding the eyepiece;

FIG. 4 is a plan view of the apparatus in which the tubes forming theparallelogram are shown in section, so as to permit the invention to bemore clearly illustrated, and

FIG. 5 is a perspective view showing the means for controlling themovement of certain optical elements from a distance.

As shown on FIG. 1, an eyepiece box 1 closed by a cover 2, carries alever 3 which controls the extension and contraction of theparallelogram linkage of the periscope. As shown in greater detail onFIG. 5, one of the two control buttons 4 and 5 turns the prism 6,

mounted in the objective box 7, and simultaneously turns at an angle ofrotation half that of the prism 6, a compensating Dove prism 8, shown onFIGS. 2-5, while the second button inserts a filter into the opticalpath.

The parallelogram linkage comprises four tubular members 9, 10, 11 and12, pivotally connected to each other and to the box 7 at the axes1313a, 14-14a and 15-1511.

The eyepiece projects through an opening in the cover 2 of the box 1,and behind the window 16 thereof may be found the milled ring 17 bymeans of which the optical device may be focussed, since it acts on thelenses 18 of the eyepiece, which are shown in FIG. 2.

The broken line X-Y represents the path followed by the rays of lightfrom the zone to :be observed to the eyepiece behind the window 16.These light rays travel in the direction of the arrows 19 found alongthe broken lines shown on FIGS. 1 and 3.

FIG. 2 shows the objective 20, the rotating prism 6, a collective pupil21, an objective 22 and a first plane mirror 23 mounted along the axis13, which transmits the bundle of light rays to a second plane mirror 24positioned on the same axis, in the tube 10, parallel to a third mirror25 also mounted in the tube 10.

Two objectives 26 and 28 and a collective pupil 27 are also positionedin the tube 10, between the mirrors 24 and 25.

Just as the two plane mirrors 23 and 24 are mounted along the pivotalaxis 13, the plane mirrors 25 and 29 (of the tube '9) are mounted on thepivotal axis 14. The plane mirror 29 is mounted rigorously parallel to aplane mirror 30 positioned on the pivotal axis 15 at the bottom of thetube 9. Between the mirrors 29 and 30 are a collective pupil 32 and twoobjectives 31 and 33.

Also on the pivotal axis -15 is a mirror 34 which refiects the bundle oflight rays to the Dove type compensating prism 8 through the objective35.

After having been reflected from the compensating prism 8, the bundle oflight rays passes into a pentagonal prism 36, in which it is twicereflected before it reaches the diaphragm 37 defining the field image,the lenses 18 of the eyepiece, and finally the exit pupil 38.

The periscope may also have its box 1 mounted to rotate about a centralvertical axis so as to permit a circular view for each position of theobjective.

A milled ring 39, shown on FIG. 1, then serves to hold the box 1,together with the remainder of the apparatus, stationary in any desiredposition.

FIG. 3 shows the lever 3 and the two control buttons 4 and whichcontrol, on the one hand, the raising and lowering of the objective and,on the other hand, the rotation of the prisms 6 and 8 and thetranslation of a filter member 40, shown on FIGS. 4 and 5, within aslideway 41.

Movement of the lever 3 turns a partially toothed gear 42, which inturn, acts through partially toothed gear 43 to swing the arm 9 of theparallelogram linkage, which is fixed to a gear 44 engaging theintermediate gear 43.

The gear ratio between the gears 42, 43, 44 is such that, for arelatively small movement of the lever 3, the tube 9 will turn 90 aroundthe axis 15, thus swinging from the horizontal to the vertical.

The milled button 4 simultaneously turns the compensating prism 8through a worm 45 which engages worm wheel 46 and the angular driveformed by the bevel gears 47 and 48.

This angular drive turns the sprocket 49 shown on FIG. 5, which sprocketdrives the sprocket 51, mounted on the axis a, through the chain 50.

The sprocket 51 is fixed to a sprocket 52 which drives another sprocket54, through a chain 53 mounted on the shaft 14a.

The sprocket 54 is fixed to a sprocket 55 shown on FIGS. 4 and 5, whichin turn drives a sprocket 57 through a chain 56. The sprocket 57controls, through the angular drive, 58, 59, the rotation of the prism6.

The milled button 5 drives a sprocket 62 through an angular drive 60,61, and sprocket 62 drives through an endless chain 63 a sprocket 6.4fixed to the sprocket 65, mounted like sprocket 64, on the axis 15a. Thesprocket 65 drives sprocket 67 through the chain 66.

The sprocket 67 is fixed to a sprocket 68, likewise mounted on the shaft14a, which drives the two sprockets 70 and 71, through the chain 69.

The sprocket 71 drives through the chain 72 a filter member 40 which maybe inserted in alignment with the pivotal axis 13, between the two planemirrors 23 and 24. This filter slides along a track 41, shown on FIG. 5.

FIGS. 3 and 4 also show that the two lower tubes 9 and 11 terminate attheir lower ends in gear teeth 73, 74, which engage with each other toensure that during rotation of the tube 9 by means of the lever 3 andthe gear train 42, 43, 44, the tube 11 turns through exactly the sameangle.

In like manner, the upper ends of the tubes 10 and 12 are fixed to twogears 75 and 76, shown in broken lines on FIG. 3, which keep the box 7in a horizontal position and insure the symmetry of tubes 10 and 12,when the parallelogram linkage is being extended or contracted.

It will, of course be appreciated that the specific em bodiment whichhas been described may be modified as to detail, improved, or added to,and that specific elements may be replaced by their mechanicalequivalents without thereby departing from the basic principles of theinvention.

In particular, the toothed portions of the gears 42, 43, 44 may beenlarged so as to transform the illustrated single-acting apparatus intoa double acting device, in which the tubes 9 and 11 swing through anangle of between an upper vertical position and a lower verticalposition.

What is claimed is:

1. An optical device comprising an objective casing containing anobjective, an eyepiece casing carrying an eyepiece, and longitudinallyextensible parallelogram linkage means connecting said casings andmaintaining the optical axes defined by said objective and eyepieceparallel at all positions of said linkage, said linkage comprising atleast one series of tubular links, one of said tubular links beingpivotally connected to said eyepiece casing and the other to saidobjective casing, and each tubular link of said series being pivotallyconnected to the next to turn about an axis parallel to said opticalaxes, and an optical system extending through said tubular links fortransmitting to the eyepiece an image formed by said objective, saidoptical system comprising at each pivotal connection of said tubularlinks a pair of mirrors, one in each of the links pivotally connected toeach other at that point, the mirrors of each link being positioned toremain parallel to each other at all positions of the links within whichthey lie.

2. An optical device comprising a first casing containing an objective,a second casing carrying an eyepiece, and parallelogram linkage meansconnecting said two casings and maintaining the optical axes defined bysaid objective and eyepiece parallel at all positions of said linkage,said linkage comprising two pairs of link members, each pair comprisinga first link pivotally connected at the end to said first casing and asecond link pivotally connected at one end to said second casing, thefirst and second links of each pair being pivotally connected to eachother, at least said first pair of links being tubular in form, eachpivotal connection constraining said links to turn about an axisparallel to said optical axes, and an optical system extending throughsaid tubular links for transmitting to the eyepiece an image formed bythe objective, "said optical system comprising at each pivotalconnection a pair of mirrors, one in each of the members pivotallyconnected to each other at that point, the

,5 v mirrors of each member being positioned to remain parallel to eachother at all positions of the members within which they lie, and meanscarried by said eyepiece casing for extending and contracting saidlinkage while said eyepiece remains stationary.

3. An optical device as claimed in claim 1 which said linkage carriesinterengaged toothed means fixed to at least two links thereof, and saidmeans for extending and contracting said linkage comprises rotatabletoothed means engaging one of said interengaged toothed means,

and a lever connected to turn said rotatable toothed means.

4. An optical device as claimed in claim 1 comprising a pivotallymounted prism positioned in said objective casing in the path of lightrays travelling from said objective to said eyepiece, and a Dove typeprism in said eyepiece casing likewise positioned in said path of travelto compensate for movements of said pivotally mounted prism.

5. An optical device as claimed in claim 4 comprising a control membercarried by said eyepiece casing and motion transmitting means housed insaid casings and linkage means for simultaneously transmitting motionfrom said control member to both said prisms.

6. An optical device as claimed in claim 5 comprising a filter slidablymounted in said objective casing for movement into and out of the pathof light rays travelling between said objective and eyepiece, anadditional control member carried by said eyepiece casing, andadditional motion transmitting means housed in said casings and linkagemeans, for transmitting motion from said additional control member tosaid filter.

References Cited UNITED STATES PATENTS 862,293 8/1907 Swasey 350 X1,309,478 7/1919 Jenkins 35052 X 1,607,688 11/1926 Perrin et a1 35022 X2,057,921 10/1936 Santoni. 2,589,363 3/1952 Foutounis 35024 X 2,966,09612/1960 DIncerti et a1. 35023 X 2,988,955 6/1961 Goto et al 35036 XFOREIGN PATENTS 769,444 3/1957 Great Britain.

913,921 12/1962 Great Britain.

637,663 4/1962 Italy.

DAVID SCHONBERG, Primary Examiner. T. H. KUSMER, Assistant Examiner.

U.S. c1. X.R. 350 52, 70, 85

